1. Field of the Invention
The present invention relates to PC card socket connector and PC cards having such socket connectors.
2. Description of the Prior Art
PC cards have a front socket connector for connection with a mating connector when it is inserted into equipment. As shown in FIG. 5, for example, a conventional PC card 51 have a metal ground plate 53 with a plurality of semi-circular projections 52 provided in the outer face of a front end portion. The semi-circular projections 52 projects from the ground plate 53 so as to make sure contact with a shield plate of the mating connector. Since it is desirous to shield the entire PC card 51, an outer metal panel 54 is provided. However, the panel 54 has a cutout portion 54A in the front end portion so as to expose the semi-circular projections 52.
As shown in FIG. 6, the PC card 51 has a socket connector 55 at the front end for connection with a mating connector 71. The socket connector 55 has a number of female contact elements 56 (of the rectangular cylinder type) arranged in two tiers in a direction perpendicular to the sheet for connection with male connector elements 72 of the mating connector 71. The contact elements 56 have upper and lower tongue portions extending diagonally rearwardly from the front edge to make sure contact with the mating contact element 72. A contact portion 56A extends rearwardly from the rear end of each contact element 56 for contact with a corresponding signal circuit provided on an inner board 58. Ground circuits are provided between the signal circuits arranged on the inner board 58 in a direction perpendicular to the sheet.
The ground plate 53 provided on the upper face of a housing 57 has a ground terminal 53A which is bent diagonally downwardly at the back of the semi-circular projections 52 to make resilient contact with the ground circuit of the inner board 58. The ground terminal 53A runs under the panel 54 from the cutout portion 54A of the panel 54.
A shield plate 73 is provided on the mating connector 71 so as to have a front contact portion folded back into the PC card receiving recess 74.
As shown in FIG. 7, when the PC card 51 is connected to the mating connector 71 by the socket connector 55, the contact elements 56 of the PC card are brought into contact with the contact elements 72 of the mating connector 71 while the semi-circular projections 52 of the ground plate 53 are brought into contact with the contact portion 75 of the shield plate 73 so that the ground circuit of the PC card are grounded through the shield plate 73 and the ground plate 53.
Since the thickness of PC cards is regulated by the standards, it is necessary to provide the panel 54 with the cutout portion 54A where there is the ground plate 53 of the socket connector 55. Consequently, there is no shielding at a gap between the ground plate 53 and the cutout portion 54A of the panel 54. In addition, the cutout portion 54A reduces the strength of the panel 54. Moreover, the cutout portion 54A permits dust and/or water to enter. Also, it makes the appearance poor.